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v3.19.3

Segments of Operations - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) segment | Sep. 30, 2018 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of segments | segment |  |  | 3 |
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Special charges to increase asbestos and environmental reserves | $ 11 | $ 9 |  |
Special Asbestos and Environmental reserve charges |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net increase (decrease) in the provision for claims of prior years |  |  | $ 18 | $ 18
Special Asbestos and Environmental reserve charges | Property and Casualty Insurance | Other lines |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net increase (decrease) in the provision for claims of prior years | $ 18 | $ 18 | $ 18 | $ 18

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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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